<template>
	<view class="u-wrap">
		<!-- 搜索框 -->
		<view class="u-search-box">
			<u-search placeholder="输入商品名称" v-model="keyword" @custom="getSearchData" @clear="clearSearch"></u-search>
		</view>
		<view class="u-menu-wrap">
			<!-- 左侧滚动区域 -->
			<scroll-view scroll-y scroll-with-animation class="u-tab-view menu-scroll-view" :scroll-top="scrollTop">
				<block v-for="(categoryitem1,categoryindex1) in category" :key="categoryindex1">
					<!-- <text class="u-line-1">{{categoryitem1.name}}</text> -->
					<view v-for="(categoryitem2,categoryindex2) in categoryitem1.children" :key="categoryitem2.id" class="u-tab-item"
						:class="[current==categoryitem2.id ? 'u-tab-item-active' : '']" :data-current="categoryitem2.id"
						@tap.stop="swichMenu(categoryitem2.id)">
						<text class="u-line-1">{{categoryitem2.name}}</text>
					</view>
				</block>
				
			</scroll-view>
			<!-- 右侧滚动区域 -->
			<block>
				<scroll-view scroll-y class="right-box" @scrolltolower="scrolltolowerEvent">
					<!-- 没有商品时显示 -->
					<template v-if="!goodsList.length">
						<u-empty text="暂无商品" mode="list"></u-empty>
					</template>
					
					<view v-else class="page-view">
						<view class="class-item">

							<!-- <view class="item-title">
								<text>{{item.title}}</text>
							</view> -->
							<view class="item-container">
								<!-- 循环的商品列表 -->
								<navigator class="thumb-box u-p-r-40 u-p-l-40 u-m-t-60" v-for="(item1, index1) in goodsList" :key="index1"
									:url="`/pages/goods/show?id=${item1.id}`">
									<image class="item-menu-image" :src="item1.cover_url" mode=""></image>
									<view class="item-menu-name">{{item1.title}}</view>
								</navigator>
							</view>
						</view>
					</view>
				</scroll-view>
			</block>
		</view>
	</view>
</template>

<script>
	// import classifyData from "@/common/classify.data.js";
	export default {
		data() {
			return {
				category: "",//分类数据
				goodsList: "",//商品列表
				scrollTop: 0, //tab标题的滚动条位置
				current: null, // 预设当前项的值
				menuHeight: 0, // 左边菜单的高度
				menuItemHeight: 0, // 左边菜单item的高度,
				keyword: '',//搜索关键字
				page:1,//分页,
				isLast:false,//是否最后一页
			}
		},
		computed: {

		},
		onLoad() {
			this.getData();
		},
		methods: {
			//请求搜索的数据
			async getSearchData(){
				this.page=1,
				this.getData();
			},
			//请求商品数据
			async getData() {
				const params={
					page: this.page,
					title:this.keyword
				}
				if(this.current){
					params.category_id=this.current;
				};
				//判断是否有分类id
				const res = await this.$u.api.goodsList(params);
				console.log(res);
				this.category = res.categories;
				this.goodsList = res.goods.data;
			},
			getImg() {
				return Math.floor(Math.random() * 35);
			},
			// 点击左边的栏目切换
			async swichMenu(c2id) {
				if (c2id == this.current) return;
				this.current = c2id;
				console.log(this.current);

				// 如果为0，意味着尚未初始化
				if (this.menuHeight == 0 || this.menuItemHeight == 0) {
					await this.getElRect('menu-scroll-view', 'menuHeight');
					await this.getElRect('u-tab-item', 'menuItemHeight');
				}
				// 将菜单菜单活动item垂直居中
				// this.scrollTop = index * this.menuItemHeight + this.menuItemHeight / 2 - this.menuHeight / 2;
				this.page=1;
				this.getData();
			},
			// 获取一个目标元素的高度
			getElRect(elClass, dataVal) {
				new Promise((resolve, reject) => {
					const query = uni.createSelectorQuery().in(this);
					query.select('.' + elClass).fields({
						size: true
					}, res => {
						// 如果节点尚未生成，res值为null，循环调用执行
						if (!res) {
							setTimeout(() => {
								this.getElRect(elClass);
							}, 10);
							return;
						}
						this[dataVal] = res.height;
					}).exec();
				})
			},
			//点击清除icon
			clearSearch(){
				this.page=1;
				this.keyword='';
				this.getData();
			},
			//触底事件
			async scrolltolowerEvent(e) {
				if(this.isLast) return;
				// console.log(e);
				this.page=this.page+1;
				const res = await this.$u.api.goodsList({
					page:this.page
				});
				this.isLast=res.goods.next_page_url?false:true;//判断是否没有数据了
				this.goodsList=[...this.goodsList,...res.goods.data]//追加数据
			}
		}
	}
</script>

<style lang="scss" scoped>
	.u-wrap {
		height: calc(100vh);
		/* #ifdef H5 */
		height: calc(100vh - var(--window-top));
		/* #endif */
		display: flex;
		flex-direction: column;
	}

	.u-search-box {
		padding: 18rpx 30rpx;
	}

	.u-menu-wrap {
		flex: 1;
		display: flex;
		overflow: hidden;
	}

	.u-search-inner {
		background-color: rgb(234, 234, 234);
		border-radius: 100rpx;
		display: flex;
		align-items: center;
		padding: 10rpx 16rpx;
	}

	.u-search-text {
		font-size: 26rpx;
		color: $u-tips-color;
		margin-left: 10rpx;
	}

	.u-tab-view {
		width: 200rpx;
		height: 100%;
	}

	.u-tab-item {
		height: 110rpx;
		background: #f6f6f6;
		box-sizing: border-box;
		display: flex;
		align-items: center;
		justify-content: center;
		font-size: 26rpx;
		color: #444;
		font-weight: 400;
		line-height: 1;
	}

	.u-tab-item-active {
		position: relative;
		color: #000;
		font-size: 30rpx;
		font-weight: 600;
		background: #fff;
	}

	.u-tab-item-active::before {
		content: "";
		position: absolute;
		border-left: 4px solid $u-type-primary;
		height: 32rpx;
		left: 0;
		top: 39rpx;
	}

	.u-tab-view {
		height: 100%;
	}

	.right-box {
		background-color: rgb(250, 250, 250);
	}

	.page-view {
		padding: 16rpx;
	}

	.class-item {
		margin-bottom: 30rpx;
		background-color: #fff;
		padding: 16rpx;
		border-radius: 8rpx;
	}

	.item-title {
		font-size: 26rpx;
		color: $u-main-color;
		font-weight: bold;
	}

	.item-menu-name {
		font-weight: normal;
		font-size: 24rpx;
		color: $u-main-color;
	}

	.item-container {
		display: flex;
		flex-wrap: wrap;
	}

	.thumb-box {
		width: 33.333333%;
		display: flex;
		align-items: center;
		justify-content: center;
		flex-direction: column;
		margin-top: 20rpx;
	}

	.item-menu-image {
		width: 120rpx;
		height: 120rpx;
	}
</style>
